Tire-repair knife



Oct. 18, 1927. 6

J. M. NEWTON TIRE REPAIR KNIFE Filed Jan. 5, 1 2

Patented Oct. 18, 1927.

UNITED STATES PATENT OFFICE.

JOHN M. NEWTON, OF SIOUX FALLS, SOUTH DAKOTA.

TIRE-REP Application filed January tire and simultaneously lifting of the edge if the layer so that the latter canbe grasped by pliers.

Heretofore it has been the custom to first use a knife to cut through the fabric layer and to then employ a separate pointed hook instrument to lift the edge of the cut por -tion, the present invention aiming to provide a simple single tool which performs both operations at one and the same time. 7

In the drawings Fig. 1 is a front si vention;

Fig. 2 is a similar enlarged detail view of the blade per se Fig. 3 is a section on line 33 of Fig. 1;

Fig. 4 is a section on line 4-4 of Fig. 1;

Fig. 5 is a rear edge elevation, and

Fig. 6 is a rear side elevation of the blade per se.

In proceeding in accordance with the present invention, a handle 1 is employed and to which the invention is applied. The device embodies a shank 2 secured to the handle and having its lower end bent at sub stantially a right angle to form a combined cutter and lifter 3 as will be nowdescribed.

As shown in Fig. 4;, the blade 3 is of somewhat V-form having its outer side curved toward the front of the blade and notched at 46, while the shank 2 has a front vertical edge 5 curved inwardly and sharpened to a knife edge as indicated at 6. A notch 8 of de elevation of the in-.

V-shape is formed at the inner side of the.

shank 2 and cooperates with or merges into notch 4 to form one side of a V-shaped cutting point 9, the opposite side of which point 9 is formed by notch 4. The blade 3 has an inclined bottom 10 and an inclined top 11, the top and bottom inclining toward the point 9 thereby providin a shoe which as is evident from Fig. 3, li s the cut la er L AIR KNiFE.

a, 1927. Serial No. 158,729.

The top and bottom of the shoe and blade are bevelled to form a curved knife edge 12, which latter cuts the layer L to a degree. of

width so as to permit the cut edge to be 7 gripped by pliers and removed.

forced'into the tire by holding the shoe at ting edges 12 and'6 enter into action and cut the layer along right angular lines X and Y as shown in Fig. 3. The notch 8 permits'the out Y to be more easily madeand also effects a cleaner out.

From. the foregoing it will be seen that the cut is effected by three edges 9, 5 and 12, all

' of which act simultaneously and at the same time the out layer is lifted. The device can be easily made, since it is merely necessary to bend the free end of the strip 2 at right angles to shape same by grinding or otherwise. I

g It is to be also notedthat the V-point 9 is located between the horizontal cutting ,edge '12 and the vertical cutting edge 6 so that the point '9. enters into action before the edges G'and 12 thus effecting a gradual out without danger of tearing the fabric.

What is claimed is Ina tire repair tool, a combined cutter and layer lifter embodying a shank having a free end bent outwardly at'substantially right anglesto form axblade, said blade having a curved outer side edge sharpenedto In operation, the V-point 9 is initially form a horizontal curved knife edge, the

front end of the horizontal part of the blade vertical and sharpened on its sides to provide a curved knife edge disposed adjacent to the V-shaped cutting point, and the rear side of the shank being formed with a V- notch which forms a side of said V-shaped cutting point, the V-shaped cutting point being locatedbetween the curved vertical and horizontal'knife edges. g

In testimony whereof I afiix my signature. v v

JOHN M. NEWTON 

